The Braves play the league-leading Philadelphia Phillies tonight at 7 p.m. ET, while the Cardinals play the Houston Astros at 8 p.m. ET. A combination of a win and a loss by the contending teams puts the winner into the postseason. Two wins or two losses results in a one-game playoff between the Braves and the Cardinals in St. Louis.

It's the same scenario in the American League, only it's Tampa Bay playing the first-place New York Yankees at 7 p.m. ET and the Red Sox playing the Baltimore Orioles at 7 p.m. ET.

Boston came into the season as the consensus favorite to win the World Series, while the Braves were picked by many to be the National League's wild card team. At the beginning of September it looked like a sure thing that both would cruise into the playoffs. The Braves were 8.5 games up on St. Louis at the beginning of the month, while the Red Sox were up by a similar margin.

Then Boston stepped off a cliff, going 7-19 for the month. Atlanta mirrored that collapse, going 9-17 in September. On the flip side, Tampa Bay is 16-10 and St. Louis is 16-8 in the same period.

Needless to say, reactions in Atlanta and Boston have tended toward dismay, disgust and self-doubt.

Jeff Schultz at the Atlanta Journal-Constitution posted a piece today titled "Poll: Who should get most blame for Braves' collapse?" in which he runs through the potential scapegoats, including General Manager Frank Wren and first-year Braves manager Fredi Gonzalez. Schultz is still not ready to give his own answers as to the source of the team's troubles.

"I've got my own feelings on this. But to be honest, I think I'm still in shock over the developments and, well, I'm still processing it all. A column will be forthcoming at some point. For now, I wanted to get your thoughts and post a poll on the topic."

"During the Red Sox's soul-crushing September swoon, fans have watched in horror as a team that looked like baseball's best collapsed like a dying star."

"The meltdown, which despite last night's win could still cost the team a once all-but-certain playoff berth, has left fans apoplectic."

"Some, their spirits beaten down by the blur of defeats, say they feel like boxers who have taken too many punches. No mas, they say. They have nothing left to give. Others have maintained a flicker of faith to carry them into tonight's finale. All agree this month has been a nightmare, a slow-drip poison that has turned a promising season into pure pain."

As you might suspect, they're singing a different tune in St. Louis. Bernie Miklasz on Stltoday.com says to "Believe in Carp," the Cards' starting pitcher tonight.

"With Adam Wainwright on the DL, there's no Cardinals pitcher you'd rather see on that mound in Houston tonight than Chris Carpenter. There may be better starters in the NL, there are guys with more impressive statistics. But Carpenter, the raging and aging bull, will give this team and its fans everything he has. He'll leave nothing out there. Tony La Russa may have to zap Carpenter with animal tranquilizer to get him out of Wednesday night's game."

That's confidence, something that's also on tap in Tampa, where Gary Shelton writes in the "Rays' season of wonder" that it had to be this way.

"And so it comes down to the final day. Of course it does. After all the surges, after all the slips, after a season that reads like pulp fiction, how else would you expect this Rays season to end? It will come down to the final game for a playoff spot, and perhaps the final out, because anything else would not make sense. Not after the Rays' historic comeback. Not after the Red Sox's monumental collapse. Not after the Improbable Dream. This season has always been destined for the final heartbeat, the way the movies always come down to the final showdown in the street, or the final sword fight on the walls of the castle, or the final farewell at the airport. Seasons such as this one do not end in Game 144 or in Game 148. They go the full 162. Or in this case, maybe 163. 'If you are scripting this one,' said Rays owner Stu Sternberg, 'you script it to the end.'"

Going up? Going down? Going to play tomorrow? It'll be decided tonight, when bubbles may burst or suffering fans may be finally put out of their misery.

(Full disclosure: The author of this post has been a fan of the Atlanta Braves since 1978 and is, indeed, suffering at this moment. Relief will come one way or the other.)